Background: The goal was to investigate the prognostic values of metastatic lymph node number (MLNn) and ratio (MLNr) for gastric neuroendocrine carcinoma (GNEC) patients treated by neoadjuvant chemoradiotherapy combined with total resection of lesser curvature.
Methods: Seventy-three patients were admitted between August 2018 and August 2021 to receive neoadjuvant chemoradiotherapy combined with total resection of lesser curvature were retrospectively analyzed. The indicators of lymph node involvement, including pathological N (pN) stage, MLNn, MLNr, and metastatic lymph node station (MLNs), and other clinicopathological data were analyzed.
Results: Of the 54 eligible patients, 44 (81%) had lymph node metastasis. The median survival time of the whole cohort was 63.2 months (14 - 153 months), and the 3- and 5-year survival rates were 88.9% and 47.9%, respectively. The medians of lymph nodes, MLNn, and MLNr were 19 (10 - 56), 5 (1 - 21), and 25% (6% - 100%), respectively. Cox regression analysis showed that pN1 (p = 0.0266), MLNn > 2 (p = 0.0091), MLNr > 0.1 (p = 0.0031), MLNs = 2 (p = 0.0119) and distant metastasis (p = 0.0021) were independent influencing factors for prognosis.
Conclusions: In addition to pN stage, the indicators of metastatic lymph node involvement, including MLNn, MLNr, and MLNs are significant predictors for the survival of patients with GNEC, and distant metastasis is also a key prognostic factor. These indicators are crucial supplements to survival factors and can improve the risk classification of GNEC patients.